JP2020188926A - Skin graft prosthesis/buffer member for auricle skin defective part - Google Patents

Abstract

To provide as a scaffold to be used for preventing defects of skin graft in defects of the perichondrium/periosteum and the subcutaneous tissue.SOLUTION: A dried amnion is produced by specific drying treatment, i.e., a pressure-reducing operation of continuously heating a raw amnion put in a treatment vessel with an infrared heater provided in a treatment vessel, and reducing the pressure of the inside of the treatment vessel, and a pressure-recovery operation of slightly raising the inside of the treatment vessel in a pressure-reduced state to an atmospheric pressure side, and irradiating the raw amnion with microwaves also from a microwave generator provided in the treatment vessel so as to perform drying while adding energy to water molecules existing in the amnion. The amnion which is dried by repeating the operations a plurality of times while maintaining a cell/tissue structure is provided as a scaffold to be used for preventing defects of skin graft in defects of the perichondrium/periosteum and the subcutaneous tissue so as to enhance healing effect by the skin graft.SELECTED DRAWING: Figure 3

Description

The present invention relates to a filling / cushioning member used for skin grafting on a pinna skin defect.

It is known that skin grafting on the defect after skin grafting makes it difficult for some parts to survive due to the onset of cancer or the like. In auricular cancer (basal cell carcinoma), even if skin grafts are performed on the auricular skin defect, infection is likely to occur and often does not engraft.

Amniotic membrane has been used as a useful dressing for refractory wounds.

JP-A-2007-54015

Gruss, J.S. & Jirsch, D.W. Human amniotic membrane: A versatile wound dressing. Can. Med. Assoc. J. 118, 1237-1246 (1978). Okabe, M. et al. Hyperdry human amniotic membrane is useful material for tissue engineering: Physical, morphological properties, and safety as the new biological material. J. Biomed. Mater. Res. --Part A 102, 862-870 (2014) ..

The amniotic membrane is a tough biological membrane composed of collagen and elastic fibers, and the raw amniotic membrane has been reported as a useful covering material for trauma and burns (Non-Patent Document 1).
However, it was only used in a limited way in actual clinical practice because it was not immediately available when needed and it was complicated to store and handle. On the other hand, dried amniotic membranes (hyper-dried human dried amniotic membranes: hereinafter, HD amniotic membranes) produced by a specific drying treatment have been reported (Patent Document 1, Non-Patent Document 2).

Due to the onset of cancer, skin grafting is performed on the defective part due to auricular skin removal, but it may be difficult to survive depending on the part. In particular, in auricular cancer (basal cell carcinoma), even if skin grafts are performed on the auricular skin defect, infection is likely to occur and often does not engraft.
For perichondrium and subcutaneous tissue defects NPWT, a foam material such as polyurethane is placed on the wound, covered with a film material so as to cover the entire wound, and then a continuous negative pressure is applied to the covered wound. It is a method of wound management that promotes wound healing.
In this study, the advantage of this method was that a good scaffold could be formed by placing the hyperdry amniotic membrane on the exposed cartilage due to defects in the perichondrium and subcutaneous tissue.
So far, there is no material that has a poor skin graft and has the effect of directly promoting healing, and only avoids necrosis of the affected area.

The inventors have clarified that the function of HD amniotic membrane as a scaffold of cells and promotion of tissue regeneration are involved in skin graft engraftment, and have completed the present invention.

According to the filling / buffering member according to the present invention, it is a restoration material used for planting a skin defect in the ear canal, and is a dried amniotic membrane obtained by drying a raw amniotic membrane wrapping an animal foetation including a human. The dried amniotic membrane is dehydrated and dried so that it can be stored in a sterile dry air, and the amniotic membrane rehydrated by immersing it in water or a buffer solution includes epithelial cells and basal membranes constituting the raw amniotic membrane. , And a dry amniotic membrane that retains connective tissue.
By adopting this configuration, skin graft engraftment is promoted by the active action of the wound healing promoting action.
Further, it may be a filling / cushioning member used for skin grafting.

By using the filling / buffering member of the present invention in skin grafting of a perichondrium defect and a subcutaneous tissue defect, skin grafting can be promoted by the active action of the wound healing promoting action of the amniotic membrane.

The figure explaining the skin grafting for the first time after the removal of auricular cancer (basal cell carcinoma). Excision was performed and skin grafts were performed on the auricular skin defect. One and a half months later, the pathological results showed that the cancer remained, the cartilage was exposed, the necrotic part was infected, and the skin graft part did not survive with the pus flowing out. The figure explaining the removal of recurrent basal cell carcinoma. 1. 1. With a safety margin, tissue is collected all around the outside and submitted for rapid pathological diagnosis. It was confirmed that there were no cancer cells. 2. 2. Under the endoscope, an incision was made in the external auditory canal skin slightly before the eardrum. A surgical margin on the ear canal side was created. The figure explaining the skin graft to which HD amniotic membrane was applied. (A) HD amniotic membrane was applied on the ear canal and auricular cartilage. (B) Skin grafting was performed on the HD amniotic membrane. The figure explaining the treatment result by the skin graft of HD amniotic membrane application. Two months later, the skin grafts were engrafted and were in good condition. A drying device that creates HD amniotic membrane.

(Outline of this embodiment)
The dried amniotic membrane produced by a specific drying treatment (hyperdry) is, for example, the dried amniotic membrane described in Patent Document 1. That is, a decompression operation in which the raw amniotic membrane placed in the treatment tank is continuously heated by an infrared heater provided in the treatment tank to put the inside of the treatment tank in a decompression state, and a slight amount in the treatment tank in the decompression state. At the time of the decompression operation to raise the pressure to the atmospheric pressure side, the raw amniotic membrane is also irradiated with microwaves from the microwave generator provided in the treatment tank to dry the amniotic membrane while applying energy to the water molecules existing in the amniotic membrane. In the dried amniotic membrane (HD amniotic membrane) produced by repeating this multiple times, the amniotic membrane cells themselves are inactivated, but the cell / tissue structure is retained.

For auricular cancer (basal cell carcinoma), excision was performed at another department, and skin grafts were performed on the auricular skin defect, but cancer remained in the affected area, causing partial infection and not engrafting (Fig.) 1).
A safety margin was taken from the previously removed site, and after confirming that no cancer remained by rapid pathological diagnosis, the cancer was removed as a mass (Fig. 2). After applying the HD amniotic membrane to the exposed auricular cartilage surface (Fig. 3a), the collected skin is grafted on it (Fig. 3b).
After 2 months, the postoperative course is good (Fig. 4).
In the present embodiment, the HD amniotic membrane is placed as a filling / buffering portion in the perichondrium defect portion and the subcutaneous tissue defect portion. By arranging the HD amniotic membrane as a scaffold between the perichondrium defect and the subcutaneous tissue defect and the skin graft, the wound healing promoting action of the amniotic membrane and the active action such as scaffold formation are promoted.

-Production of HD amniotic membrane The raw amniotic membrane was dried under the conditions of the following vacuum, far-infrared, and microwave devices using the drying device shown in FIG.
・ Drying tank heating: 50 ℃, FIR: 50 ℃, Stop valve: 37%, Maximum ultimate pressure 0.34kPa Empty operation Maximum ultimate pressure 0.33kPa
・ Drying method (1) Decompression 180sec
(2) Restoration pressure 30 seconds (stop valve opening 37%)
Microwave input 0.1kw-180sec (recovery continues)
(3) Decompression 180 sec
After (4), repeat (2) and (3) (5) Finish drying by checking the ultimate pressure after 180 sec decompression of (3) (0.30 to 0.35 kPa) and manually.
Restored to atmospheric pressure and finished

The dried amniotic membrane (HD amniotic membrane) produced by a specific drying treatment, that is, the raw amniotic membrane placed in the treatment tank, is continuously heated by an infrared heater provided in the treatment tank to reduce the pressure inside the treatment tank. During the decompression operation and the decompression operation to slightly raise the inside of the processing tank in the depressurized state to the atmospheric pressure side, the raw amniotic membrane is also irradiated with microwaves from the microwave generator provided in the treatment tank to enter the amniotic membrane. Drying is performed while applying energy to the existing water molecules. The amniotic membrane dried while retaining the cell / tissue structure by repeating this a plurality of times has improved storage stability and is easy to handle. By using this HD amniotic membrane as a scaffold used for the purpose of preventing poor skin grafting when the perichondrium / periosteum is defective and the subcutaneous tissue is defective, the healing effect of skin grafting can be enhanced.

10 Processing tank 12 Rotating table 14 Far-infrared heater 16 Motor 18 Vacuum pump 20 Solenoid valve 22 Decompression pipe 24 Filter 28 Decompression pipe 30 Microwave irradiation device

Claims (2)

A restoration material used for implanting a skin defect in the ear canal, which is a dry amniotic membrane obtained by drying a raw amniotic membrane that encloses a foetation of an animal including a human, and the dried amniotic membrane is in a sterile dry atmosphere. The amniotic membrane that has been dehydrated and dried for storage and rehydrated by immersing it in water or a buffer is a dried amniotic membrane that retains the epithelial cells, basal membrane, and connective tissue that make up the raw amniotic membrane. A filling / buffering member for amnion and subcutaneous tissue, which is characterized by being present. The filling / cushioning member according to claim 1, which is used for skin grafting of a pinna skin defect.